Convert PAL to NTSC with VirtualDubMod

If you want to create a video file that can be burned as an NTSC compatible disk, you need to convert the file you just created with VLC Player. PAL DVD video is typically 720×576 at 25fps. NTSC is generally 29.97fps and 720×480, but in this case we’re going to cheat a little in making a file. A commonly supported video format is 24fps at 720×480. Slowing down the 25fps video from the PAL file to 24fps gets you a viewable result without too much complex math. To make this conversion, we need another video app called VirtualDubMod.

First VirtualDubMod imports the .mpg file we created, which may take several minutes.

After importing the video, we need to apply a number of filters to the file in order to process the PAL to NTSC conversion correctly.

From the Video menu, make sure Full processing mode is selected.

Choose Filters from the Video menu and click the Add button.

For interlaced content, choose the Deinterlace filter, double click it and choose the Blend fields together option. If your video is progressive content you can skip this filter.

Next add the Levels filter. Because the gamma on PAL content is generally 20% higher than NTSC, put the result of 1 divided by 1.2 in the input level, which is 0.833333.

Finally add the resize filter and set it to 720×480 with the Lanczos3 filter mode.

We’re not quite done with the settings yet. Now we need to make changes to the Audio before converting. From the Streams menu, choose Stream list.

Right-click the audio file and verify full processing mode is on. Select Use advanced filtering from the right-click menu, to make sure it is checked. Now select Filters and choose Add. First add the input filter. Next add the stretch filter. Double click the stretch filter to add the stretch ration. To keep the audio in sync with the video, we have to slow it down just a little. The PAL audio is set to match up with a 25fps video speed. We’re converting the file to 24fps, so we need the audio to correspond. To get a matching audio, divide 25 by24 and use the result in an audio stretch filter. This translates to 1.0416666. Last add the output filter.

The final thing you need to add to the video processing settings is a frame rate. Choose Video > Frame Rate from the menu, click the button next to Change to and put 24 in the box.

If you plan to convert several PAL files to NTSC, choose Save Processing Settings from the File menu to store all these settings for later.
Now choose Save As from the file menu and either pick a compressed AVI format like DivX from the list of choices or save an uncompressed AVI file. This is the file you will use to make a DVD later.